ScienceShot

ScienceShot: Crystal Clear Nano-Gold

Superman has nothing on Jianwei Miao, at least in the vision department. Miao, a physicist at the University of California, Los Angeles, and his colleagues have developed a way to image any type of nanoparticle with unprecedented accuracy. In the picture above, the technique, called electron tomography, shows a gold nanoparticle made up of 3871 atoms. Inside the nanoparticle, the researchers could easily resolve multiple "grains" (green, gold, blue, and red) in which atoms in each grain share a common atomic alignment that is offset from neighboring grains. The technique also manages to spot many, though not all, individual atoms throughout the nanoparticle. Like a CT scan for nanoparticles, electron tomography takes dozens of snapshots of an object, slightly rotating the camera and detector with each shot. It then uses computer algorithms to stitch the image together in one composite picture. Previous electron tomography efforts have managed to resolve images down to a cube one nanometer on each side—but they could image only particles in which all the atoms are in a rigid lattice, not with separate grains, or with no defined orientation at all. Miao and colleagues report in this week's Nature that by improving their image-collection techniques, they could image any particle, although their overall resolution is slightly less than the previous record. No word yet on whether Miao has something in the works to leap over tall buildings in a single bound.